Supplemental carburetor



June 25, 1957 H. T. LUCAS 2,797,072 Y SUPPLEMENTAL CARBURETOR Filed'Sept. 20, 1954 2 Sheets-Sheet 1 Fig. 22 f E Harold Z' Lucas 1 INVENTOR.

June 25, 1957 H. T. LUCAS 2,797,072

SUPPLEMENTAL CARBURETOR Filed Sept. 20, 1954 2 Sheets-Sheet 2 Harold 7. Lucas INVENTOR.

United States Patent 2,797,072 SUPPLEMENTAL CARBURETOR Harold T. Lucas, Decatur, Ill., assignor of one-half to Ralph Anderson This invention relates generally to charge forming devices for internal combustion engines and pertains more particularly to a device to supplement the mixing action of a conventional carburetor.

A disadvantage accruing from the use of conventional carburetors for internal combustion engines is the difficulty of supplying a proper air-fuel mixture to the engine, particularly during starting of the same, this condition being aggravated as the ambient air temperature is lowered. The chief difficulty under these circumstances is that the raw gasoline which is fed into the carburetor does not sufficiently vaporize to supply a proper air-fuel mixture 'to all of the cylinders of the engine. Consequently, engine starting under these conditions is difficult, and it frequently occurs that the raw gasoline will form in pools or puddles in the manifold, sometimes to such an extent to cause the condition known as flooding. Further, when an engine has reached operating tempera ture, ;to provide flexibility to the engine, it is necessary to heat the air-fuel mixture, usually by a hot spot in the intake manifold upon which exhaust gases are directed, in order to sufiiciently volatilize the fuel and create a homogeneous air-fuel mixture which will provide proper combustion in all of the cylinders of the engine. However, due to the raised temperature of the air-fuel mixture .as created 'by'such intake manifold hot spots, the volumetric efficiency of the engine drops with attendant decrease in gas mileage and power.

It is therefore an object of this invention to provide improved means for supplying a homogeneous air-fuel mixture to the cylinders of an internal combustion engine.

It is a further object of this invention to provide a supplemental carburetor for use in conjunction with a conventional carburetor of an internal combustion engine to assure a homogeneous air-fuel mixture to the cylinders of an associated internal combustion engine and to supply such air-fuel mixture at a lower temperature than that which the engine is operated upon without the supplemental carburetor, so as to increase the volumetric efiiciency of the engine to produce a more powerful and economical engine.

Another object of this invention is to provide a supplemental carburetor for internal combustion engines which incorporates a tank or receptacle member into which a predetermined amount of fuel is introduced and in which a fan is disposed to cause violent agitation of the air-fuel mixture therein.

These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout, and in which:

Figure 1 is a side elevational view of an internal combustion engine showing the invention in use thereon;

Figure 2 is an enlarged horizontal section taken substantially along the plane of section line 2-2 in Figure l;

Figure 3 is an enlarged vertical section taken through the supplemental carburetor;

Figure 4 is a horizontal section taken substantially along the plane of section line 44 of Figure 3; and

Figure 5 is an enlarged sectional view through the float valve mechanism of the supplemental carburetor.

Referring now more particularly to the drawings, the reference numeral 10 indicates generally an internal combustion engine which incorporates the usual intake manifold assembly 12 and the exhaust manifold assembly 14, the latter having an exhaust pipe 16 leading therefrom. The engine also utilizes a conventional fuel pump assembly 18 and an outlet 20 leads therefrom for connection to the carburetor assembly 22 mounted upon the intake manifold 12, this carburetor being of entirely conventional construction and the details of which are not herein shown or described inasmuch as the conventional carburetor itself forms no part of this invention. The fuel pump outlet line 20 also leads to the supplemental carburetor which is indicated generally by the reference character 24. The internal combustion engine also includes a fan belt pulley member 26 attached to the forward projecting end of the crankshaft 28 and a belt member 30 is trained about this pulley and about a pulley 32 on the fan and water pump assembly for purposes well understood in this art.

Referring now more particularly to Figure 3, the supple mental carburetor 24 will be seen to consist of a receptacle or casing member formed of the upper and'lower sections 34 and 36, respectively, each of which is provided with an annular flange, such as those indicated by the reference characters 38 and 40, through which fastening members 42 are projected for the purpose of removably securing the sections together.

Both the. top and bottom sections of the receptacle or tank are preferably formed of cylindrical configuration, and it will be seen that the lower section 36 is provided with a bottom wall member 44 whereas the top section 34 is provided with a removable cover member 46, the connection between the upper section 34 and the cover 44 being similar to the connection between the upper and lower sections. Mounted within the lower section 36 is an annular baffle plate member 47, these two members being suitably secured'together, as by welding 48 or the like. The fuel inlet line to the tank communicates therewith below the bafile' plate 47 and is secured thereto in any. suitable manner with the end of the line within the tank or receptacle terminating in an L-shaped fitting member 50 provided at its upper end with a valve seat portion 52 and with car members 54 through which a pin 56 projects to pivotally secure the float rod member 58 thereto. The float rod terminates at one end in a valve disk member 60 which engages the previously described seat 52 to shut off the flow of fuel through the fitting 50, and the opposite end of the member 58 is provided with the float ball 62, the construction being obviously such as to maintain a predetermined level of fuel 64 within the bottom section 36 of the tank or receptacle 24.

An air inlet conduit 66 also communicates with the lower tank section 36 below the baffle plate 47 and is designed to direct air over the surface of the fuel 64 within the section 36. It is to be understood that suitable air filter means may be provided on the free end of the air inlet conduit 66, as is conventional.

An actuating shaft member 68 is rotatably received in the cover member 44 axially of the tank or receptacle, suitable bushings 7t) and 72 being provided for this purpose. The lower end of the shaft has rigidly attached thereto a hub disk member 74 which is of smaller diameter than the internal diameter of the lower section 36 and peripherally disposed on this disk in depending relation thereto are a series of impellers or vanes 76 such as to form what is commonly termed a squirrel cage fan. This fan is of the centrifugal type, and for the purpose of rigidifying the'blades 76, their lower ends are connected to a blade mounting ringorplate '78 'whichis of annular configuration such that its center opeiiingaligns and matches with the center opening of 'the annular bafile plate 47, as will be readily apparent fronr'a study of Figures 3 and 4. It is to be understood that any suitable means may be provided for maintaining the shaft 68'a'nd consequently the fan assembly in a' predetermined longitudinal position and to prevent longitudinal shifting of the assemblies within the receptacle or tank.

The upper end of the shaft is provided with a portion 80 of non-circular configuration in cross-section such as to be readily attachedto a flexible cable assembly 82 which extends therefrom'to' a pulley member 84 mounted upon a- Z-shaped bracket 86 secured to the engine 10, see particularly Figures 1 and 2. 'The positioning of the bracket 86 is such as to engage the pulley 84 against the outside surface of the fan belt 30 and drive the flexible shaft or cable assembly 82 and consequently cause rotation of the fan assembly Within the receptacle or tank. Adjacent the top end of the upper section 34 is an air outlet conduit 88 which is adapted for connection to the air horn of a conventional carburetor, such as that illustrated and previously described. For this purpose, the outlet conduit 88 may be provided with a downturned portion 90 terminating in a flange 92 for suitable connection to the carburetor air horn.

In operation, the fan assembly is rotated to act upon the fuel-air mixture which is occasioned by the evaporation ofthe fuel 64 as the air enters the air inlet conduit 66, and the fan causes violent agitation of all the air introduced from the lower section to the upper section and out through the outlet conduit 88 to thoroughly mix and homogenize the air-fuel mixture such as to provide a proper mixture for the various cylinders of the associated internal combustion engine. At the same time, the temperature of the air-fuel mixture is materially reduced by the rapid evaporation of the fuel 64, such as to lower the over-all temperature of the air-fuel mixture entering the internal combustion cylinders and effectively raise the volumetric efliciency thereof to increase the gas mileage and power of the engine.

It is to be noted that the assembly can be mounted directly within a gas tank of a vehicle or in the position shown in Figure 1, as desired. When mounted within the gas tank, the lower section 36 thereof is replaced by the gas tank itself, the fan serving to agitate the fumes directly from the gas tank and supply them to the carburetor assembly 22, as will be readily apparent.

From the foregoing, the construction and operation of the device will be readily understood and further explanation is believed to be unnecessary. However, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction shown and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the appended claim.

What is claimed as new is as follows:

In combination with an internal combustion engine having an intake manifold and a principal carburetor disposed in communication therewith for supplying a combustible mixture thereto, said principal carburetor having an air intake throat, a supplemental carburetor mounted adjacent the principal carburetor, said supplemental carburetor comprising a receptacle having a bottom wall and a peripheral side wall, a fiat bafile mounted in spaced relation to the bottom wall and having an enlarged central opening therein, an air inlet conduit communicating with said receptacle below said baffie plate, a fan mounted within said receptacle above said baffle plate, a fuel supply conduit communicating with the receptacle below said air inlet conduit, float control means operatively associated with'said fuel conduit for maintaining the fuel level below the bafile plate at a predetermined level, a closure cover for said receptacle, and an air-fuel mixture outlet communicating with the receptacle above said baffle plate, said outlet connected to the intake throat of the principal carburetor for directing the air-fuel mixture discharged by the fan to the intake throat of the principal carburetor, said fan being of the centrifugal type and having the blades thereof disposed closely adjacent the upper surface of the baffle and having an inlet substantially equal in size to the baffle opening for pressurizing the receptacle above the bafile.

References Cited in the file of this patent UNITED STATES PATENTS 760,061 Dubuis May 17, 1904 1,000,518 Harris Aug. 15, 1911 2,319,119 Feinberg May 11, 1943 2,702,694 Feather'ston Feb. 22, 1955 FOREIGN PATENTS 536,116 Great Britain May 2, 1941 

